If we want rice per person, that's

1a. Answer: 25/3
That's between 24/3 and 27/3 i.e. between
1b. Answer: 8 and 9
1,000,000,000,000 is the answer
-2 = 5x +3
5x = 3 + 2
5x = 5
x = 1
You multiply it with the same number you use for the denominator.
in this case 3/4 and 7/10
you find the LCM of the denominator is 20
so for 4 to become 20 you multiply by 5 then for the numerator 3 also multiply by 5, so you get 15/20
its the same also with 7/10, you multiply both the numerator and the denominator by 2 and get 14/20
hope it help... :)